Cita APA (7a ed.)

BirdLife International, Burfield, I., Bommel, F. v., Gallo-Orsi, U., & Callaghan, D. (2004). Birds in Europe: Population estimates, trends and conservation status. BirdLife International.

Cita Chicago Style (17a ed.)

BirdLife International, Ian Burfield, Franz van Bommel, Umberto Gallo-Orsi, y Des Callaghan. Birds in Europe: Population Estimates, Trends and Conservation Status. Cambridge: BirdLife International, 2004.

Cita MLA (9a ed.)

BirdLife International, et al. Birds in Europe: Population Estimates, Trends and Conservation Status. BirdLife International, 2004.